Any but the most simple of today's robotic devices are expensive. Unfortunately, the kind of robotic devices commonly used for education in technical schools most often are dedicated to one particular use, and cannot be used simultaneously for different projects. Worse yet, because typically such projects require individual laboratory set-ups before employing the robotic device, users cannot minimize the time wasted in using a dedicated robot by, at least, setting up their experiments before approaching the robot, but must wait until the robot is free, then set up their experiment, and then execute their experiment while others wait. Similarly, if other work such as research is in progress, this must also be torn down so that these laboratory exercises can proceed. This necessitates such a technical school losing countless man hours of productivity, and can well adversely affect an instructor's morale if it is his own research work it must be repeatedly disrupted destroyed in mid-course simply to accomodate a student laboratory.
Moreover, such robotic devices are dangerous. These devices usually have at least one articulated cantilevered arm having a gripper device that, typically, has a pneumatic drive to move the gripper linearly. As such, a robotic arm swings horizontally across a work area, and with the considerable inertia carried by such an arm, an unwary worker struck by such an arm can experience considerable injury.
Additionally, the vertically moving gripper arm is, to an extent, unwieldy because these pneumatic arms conventionally have only two positions: completely up or completely down, and lack fine position control to enable a worker or student to manually position the gripper arm intermediate of its two extremes. Present robot arms are repeatable, but not accurate. That is, if a robot arm would go to one point in space responsive to a positioning command, the robot can return to that point responsive to the same command with great precision (good repeatability). However, if one would attempt to direct the arm to this point by pre-programming the point's coordinates, the robot will likely move only to the vicinity of the point (poor accuracy). For this reason, robotic routines are pre-programmed with position coordinates vacant, and these coordinates input by moving the robot by hand to the coordinates. This is called "teaching" the robot. If the robot's routine calls for manipulating small objects, or performing movements having small tolerances for error, it would be a great advantage to have fine control over the arm that must manipulate these objects so that the arm may be moved to points intermediate of its two extreme positions, thus simplifying the "teaching" process.